I used this adapter to connect a 1.25" hose to the inlet of my 18ft hose. above ground pool. The purpose was to use the pool pump as a vacuum cleaner. The inlet is just under an inch in diameter and a 1.25 inch hose will not fit. This adapter helps with this problem perfectly! The adapter is made of durable, high-quality white plastic. You have to put a hammer on him to break this puppy. This adapter also works with a 1.5 inch hose.